---
title: "CVE-2018-4063: Sierra Wireless AirLink ALEOS Unrestricted Upload of File with Dangerous Type Vulnerability"
url: https://erroneo.us/security/cve/CVE-2018-4063/
description: "CVE-2018-4063 (Sierra Wireless AirLink ALEOS): Exploited in the wild (CISA KEV). An exploitable remote code execution vulnerability exists in the upload.cgi…"
type: vulnerability-record
section: "Security Digest"
date_published: 2019-05-06
date_modified: 2026-05-22
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2018-4063"
kev: true
cvss: 8.8
epss: 0.2726
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2018-4063: Sierra Wireless AirLink ALEOS Unrestricted Upload of File with Dangerous Type Vulnerability

**Signal:** Exploited: patch now if you run it. CISA has confirmed exploitation in the wild. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Yes, if you run Sierra Wireless AirLink ALEOS. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2025-12-12, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2026-01-02 ; treat that as the outer limit, not the target.
- EPSS 27.3% , percentile 98: FIRST’s model estimates a 27.3% chance of exploitation activity in the next 30 days, higher than 98% of all scored CVEs (very high). EPSS is a probability, not a verdict.
- Needs an account (low (any account)). Exposure depends on who can log in.

## What it is

An exploitable remote code execution vulnerability exists in the upload.cgi functionality of Sierra Wireless AirLink ES450 FW 4.9.3. A specially crafted HTTP request can upload a file, resulting in executable code being uploaded, and routable, to the webserver. An attacker can make an authenticated HTTP request to trigger this vulnerability.

## Affected products (CVE record)

- n/a Sierra Wireless: Sierra Wireless AirLink ES450 FW 4.9.3

## Severity

- CISA-ADP CVSS 3.1: 8.8 `CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`

## Exploitation

- CISA KEV: added 2025-12-12; federal due date 2026-01-02. Known ransomware use: Unknown.
- CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- CISA SSVC assessment: exploitation active , automatable no , technical impact total .
- FIRST EPSS (model of 2026-10-21): 27.26% probability of exploitation activity in the next 30 days; percentile 98.

## Sources

- [Listed in CISA KEV notes (source.sierrawireless.com)](https://source.sierrawireless.com/resources/airlink/software_reference_docs/technical-bulletin/sierra-wireless-technical-bulletin---swi-psa-2019-003)
- [Listed in CISA KEV notes (source.sierrawireless.com)](https://source.sierrawireless.com/resources/airlink/hardware_reference_docs/airlink_es450_eol)
- [CVE.org record CVE-2018-4063](https://www.cve.org/CVERecord?id=CVE-2018-4063)
- [NVD entry CVE-2018-4063](https://nvd.nist.gov/vuln/detail/CVE-2018-4063)
- [CISA Known Exploited Vulnerabilities catalog entry](https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-4063)
- [Listed in CISA KEV notes (cisa.gov)](https://www.cisa.gov/news-events/ics-advisories/icsa-19-122-03)
- [packetstormsecurity.com](http://packetstormsecurity.com/files/152648/Sierra-Wireless-AirLink-ES450-ACEManager-upload.cgi-Remote-Code-Execution.html)
- [ics-cert.us-cert.gov](https://ics-cert.us-cert.gov/advisories/ICSA-19-122-03)
- [108147](http://www.securityfocus.com/bid/108147)
- [talosintelligence.com](https://talosintelligence.com/vulnerability_reports/TALOS-2018-0748)
- [forescout.com](https://www.forescout.com/blog/ot-network-security-threats-industrial-routers-under-attack/)

---
Source page: https://erroneo.us/security/cve/CVE-2018-4063/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt